I recently co-chaired, with the guidance of Edwin Lampert, an Offshore Support Journal webinar on remote dynamic positioning trials
The industry appears to want to embrace remote trials but there are different interpretations of what ’remote’ means. In addition, there are different interpretations what can be achieved now based on the degree of automation available on a vessel and what can be achieved in the future with a design to test philosophy which needs to be embraced at the start of the vessel concept phase.
OCIMF’s Dynamic Positioning Failure Mode Effects Analysis Assurance Framework Risk-based Guidance document certainly goes someway to providing some much-needed clarity but I believe the industry needs to have a few agreed definitions and an agreed framework for understanding remote trials. I propose leveraging a simple four-level framework developed from the aviation industry that could aid understanding.
Nature of testing. Ideally all testing should be objective
As Sherman wrote in relation to evidence-based management:
‘we are all entitled to our own opinions, but not our own facts’
The quote can be attributed back to D Moynihan and J Schlesinger but is no less valid in the case of dynamic positioning trials.
I have seen, and am sure others have seen, that some independent surveyors have a subjective opinion on what the results show rather than being totally objective. I am not saying that a surveyor’s subjective opinion is not valuable, at times it is where experience provides additional insight and maybe the IMCA DP practitioners scheme will reduce the number of errant subjective opinions that are provided. With paper-based systems the surveyor’s opinion relies on how the expected test result is written. Ideally with digital data the potential subjective interpretation is removed.
I believe there should be a set definition that should reflect the ultimate goal of any annual trials. For example, this could be ‘To have objective confidence that the vessel equipment is capable of performing incident free DP operations with performance, protection and detection all being objectively validated from aligned data’.
Mat Bateman raised an interesting and valid point, to paraphrase: “during attended trials it is something out the corner of your eye that you spot that you go and dig into and find there is an issue”.
I would take this to mean that something is found that is not directly within the boundaries of the test being conducted. I believe OCIMF has aimed to capture this with the statements of global and local impact. The global impact is the position keeping ability of the vessel and other affected systems. The local impact is the failure effect on the local system itself. Both have to be taken into consideration during testing and go someway to consider Mat’s point.
What is data?
The industry should define what data is. Some may take this to be anything that supports a test result. Other may interpret data to be digital data captured from the dynamic positioning, automation and data logger systems installed on board. OCIMF do provide some guidance on what is acceptable and what is not.
At the lowest level this has been interpreted to be the basics of screen shots showing position keeping pre and post-test.
At a higher level, digital data captured from the dynamic positioning and automation systems is used to provide objective evidence. This should be time series data including pre and post-test configuration, position and heading data, thrusters/sensors enabled status to objectively show the vessel reacts during the test. This would achieve alignment with OCIMF’s global impact.
At the highest level this should include detail of each system that has an influence on the positioning keeping ability of the vessel both pre & post failure. For example, when testing uninterruptible power supplies (UPS) as part of a single test, the status and battery levels should be captured as time series data for the period of the test. This would achieve alignment with OCIMF’s local impact.
A guidance framework
I would propose that the industry should consider a simple framework for determining the level of remote trials a vessel is capable of achieving. This could follow the aviation industries four levels of digital checklists which are shown below:
|1||Digital||No integration, some benefits of quick distribution and checking of missing boxes|
|2||Semi automation||Some sensor information, can highlight high level issues/changes|
|3||Full automation||Full system/sensor integration, full identification off issues/changes|
Remote trials framework
With the ultimate aim to gain objective confidence of the vessels ability to operate with incident fre-e dynamic positioning operations, the four levels of remote trials could be defined as:
|Paper||Tests are revealed shoreside. Screen shots used as evidence of position keeping pre and post test, little in the way of digital data being provided as evidence. System alignment of time stamps and test steps manually captured.|
|1||Digital||Test protocols are produced digitally and signed off electronically with screen shots captured within the digital test program. Alignment of test stamps and test steps electronically captured.|
|2||Semi automation||Time series digital data is captured to show pre and post equipment status and position keeping integrity only. Limited sensor integration, lacking detailed system configuration pre and post-test (global impact only). Alignment of test stamps and test steps electronically captured.|
|3||Full automation||Time series digital data captured to show detailed system configuration (local impact), position/heading integrity and all other system status (global impact). Alignment of test stamps and test steps electronically captured.|
It should be recognised that this framework is focused on testing. An alternative approach, which is acknowledged by OCIMF, is to have systems with self-diagnostics and self-test routines which continually report a ‘healthy to operate’ status.
There is so much more to write and consider on this subject and it is good to see that the debate is open and will hopefully provide some traction on this subject to the benefit of the all offshore industry stakeholders. I believe the industry needs a set framework to allow common interpretation of what level of remote trials are achievable.
Whether we will see classification societies offering vessel notations to show what level of remote trials can be achieved on specific vessels or industry bodies providing further guidance on the levels of remote trials is open to debate.
Watch the full ’Remote DP trials & FMEAs: What the guidelines say. What the guidelines mean’ webinar in our webinar library